Sky News host Chris Kenny says it had been put to him directly from a serving Labor MP that any inquiry into historical rape allegations might suit the supporters of Anthony Albanese worried about any potential leadership threats.

"An inquiry could kill two birds with one stone - remember, this is from the Labor side, which is trying to take the high moral ground on this horrIble and difficult issue," he said.

Labor has been hoping to force an inquiry into the historical rape allegations made against Attorney-General Christian Porter but much speculation in politics and media suggested Labor would be reticent to push for an inquiry out of fear it might result in an identical inquiry being run into the historical rape allegations against former Labor leader Bill Shorten which were dropped by Victoria police in 2014.

"The argument goes, don't attack Porter or Shorten could suffer too," Mr Kenny said.